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We have discovered two unconstrained forms of free Lagrangian for continuous spin(CS) theory in arbitrary flat spacetime dimension for bosonic case. These Lagrangians, unlike that by Schuster and Toro, do not include delta functions and are conventional. The first form consists of five kinds of totally symmetric helicity fields and one kind of gauge parameter. By introducing auxiliary creation and annihilation operators, each is combined into a state vector in Fock space, including all ranks one by one. The Lagrangian imposes no constraints, such as trace conditions, on these fields or the gauge parameter field. Additionally, the Lagrangian does not contain higher-order derivative terms. In the limit as CS parameter μ approaches zero, it naturally reproduces a Lagrangian for helicity fields in higher spin(HS) theory, known as unconstrained quartet formulation. Permitting third-order derivatives, we also obtain the second unconstrained form of Lagrangian that can be written in terms of three kinds of fields, including μ , similar to the formulation by Francia and Sagnotti. Partial gauge fixing and partial use of equations of motion (EOM) on this Lagrangian yield a Fronsdal-like Lagrangian with a single double-traceless field, including μ. By imposing further gauge fixing on the field in the EOM with respect to divergence and trace, we confirm the reproduction of the modified Wigner equations already known in literature. [ABSTRACT FROM AUTHOR]

In a Taiwan-France telecollaborative project, Beyond These Walls , we designed a self-introduction activity to facilitate connective affordance between two groups of learners. Participants selected three objects – representing their past, present, and future – to their intercultural partners. Students prepared PowerPoint files and text documents to post on a project website. Participants then read, commented on, and asked/answered questions about the postings. To understand how the participants presented and positioned themselves during the processes of forming connectivity, the object descriptions and interactive postings were collected. Bakhtin’s (1986; 1981) conceptions of audience and addressivity and the social presence theory of Gunawardena (1995) were used to analyze the data. Our findings suggest that objects reflected the participants' identities and personas, which helped to create a sense of physical presence that is frequently lacking in online communication. The acts of selecting, describing, reading, and discussing objects of personal significance were conducive to participants' awareness of one another's identities and shaped the perceptions of their interlocutors as authentic, identifiable individuals with whom interpersonal communication was possible. Based on these findings, we discuss the importance of identity and how identity construction strategies foster social presence that is essential in telecollaborative settings. [ABSTRACT FROM AUTHOR]

Abstract: Land cover and land cover change, both in time and space, were analyzed in the Gediz Delta (Turkey) and the Rhone Delta (Camargue, France) to determine the evolution of two great deltas in the Mediterranean basin. Geographical Information Systems and remote sensing were used to estimate the impact of land use changes on habitats over a 35 year period from 1975 to 2010. The first images used MSS captures from 1975 with a spatial resolution of 80 m; precision was gained from 1980 with the use of LandSat satellite images (spatial resolution of 30 m in multi-band modes) and then with satellite images from Spot 4, Spot 5 and Google Earth Pro. The images were classified using GEO Image and then analyzed and laid out with the aid of ArcGis and Quantum GIS 1.7.0 software programs. The data was verified using a confusion matrix, which provided between 85 and 95% global precision rates. This qualitative data on the evolution reveals that despite important conservation measures (including Ramsar site, National Park, and Natural Park status) both deltas have been subject to substantial changes over this time period. Important declines in natural habitats such as sansouires, beaches, dunes and reed beds have been replaced by increased areas of urbanization and annual agricultural crops. This analysis demonstrates the important pressures that continue to impact the delicate natural Mediterranean habitats and puts in evidence the need to enforce current legislation in order to conserve the deltas in the future. [Copyright &y& Elsevier]

Abstract: We study the production cross section of the t-channel single top quark at the LHC in the noncommutative space–time. It is shown that the deviation of the t-channel single top cross section from the Standard Model value because of noncommutativity is significant when . Using the present experimental precision in measurement of the t-channel cross section, we apply upper limit on the noncommutative parameter. When a single top quark decays, there is a significant amount of angular correlation, in the top quark rest frame between the top spin direction and the direction of the charged lepton momentum from its decay. We study the effect of noncommutativity on the spin correlation and we find that depending on the noncommutative scale, the angular correlation can enhance considerably. Then, we provide limits on the noncommutative scale for various possible relative uncertainties on the spin correlation measurement. [Copyright &y& Elsevier]

Abstract: Avalanches threaten mountainous regions, and probabilistic long term hazard evaluation is a useful tool for land use planning and the definition of appropriate mitigation measures. This communication focuses on avalanches counts in the French Alps, and investigates their fluctuations in space and time within a Bayesian hierarchical modeling framework.We have at our disposal a 60 year data set covering the whole French Alps. The considered time scale is the winter. The elementary spatial scale is the township. It is small enough to allow information transfer between neighboring paths and large enough to avoid errors in paths localization. Data are standardized with a variable integrating the number of surveyed paths.A hierarchical Poisson-lognormal model appears well-adapted to depict the observation process with such discrete data. The spatial and temporal effects are assumed independent, and they are considered in the latent layer of the model. The temporal trend is modeled with a cubic spline whereas different spatial dependence sub-models are tested. The latter ones work on different types of supports (continuous field and discrete grid), and at different embedded spatial scales. Model inference and predictive sampling are carried out using Markov Chain Monte Carlo simulation methods. The spatial structure explains the larger part of the relative risks. The spatial dependence is visible at the scale of townships, but with a short range. At the larger scale of the massifs, the spatial dependence is weaker.The regional coherence of the results with the number of avalanche releases suggests that we may also search for other spatially structured variables implicated in the magnitude of avalanches that could help transfer information from one path to another. [Copyright &y& Elsevier]

Abstract: What is the mechanism in creating the mass of the elementally particles? What is the origin of the dark matter which fills the universe? Is there a hidden space-time dimensions other than our ordinary 3+1? These fundamental questions that have been unanswered over the decades are finally ready to be solved with the TeV energy scale proton–proton collider, LHC (large hadron collider), with the large multi-purpose detector called ATLAS (A Toroidal LHC Apparatus). The LHC finally restarted its operation at November 2009, after a long shutdown period following the incident in 2008. This article aims to address the basic intrinsic issues of the contemporary high energy particle physics, and will illustrate how ATLAS can shed a light on them. Generic explanations on LHC and ATLAS, and also on how the Japanese group is taking part in the large international collaboration are addressed. [ABSTRACT FROM AUTHOR]

One of the main factors limiting the acceptance of large carnivores is livestock depredation. Reducing damages on livestock requires understanding how depredation varies in space and time. The conservation of the brown bear (Ursus arctos) population in the Pyrenees offers a relevant study case to illustrate this issue, with a minimum population size of 41 individuals recorded in 2016 and an average of 103.3 ± 18.9 attacks per year on domestic animals between 2010 and 2016 during the summer pasture period. We analysed the spatial aggregation of depredation events by using the local Getis-Ord analysis of spatial dependence at the management scale (pastoral units) and at a finest scale (250 × 250 m grain). Our results uncover the absence of coldspots of brown bear depredation in the French Pyrenees and the presence of significant hotspots. Depredation hotspots are consistent in time, meaning that a hotspot in one year is likely to exist in the following year(s). The fine scale analysis allowed identifying both inter- and intra-pasture hotspots and we propose a simple method to rescale these fine scale results. We linked this spatial pattern of hotspots (at 250 m resolution) to environmental factors. Hotspot presence is characterized by being close to forest and buildings with a high proportion of grassland and on steep slopes. Moreover, a nonlinear relationship with brown bear activity describes the presence of hotspots. The assessment of depredation hotspots and their link with environmental factors offers some practical guidance about where to focus efforts in order to decrease this human-large carnivore conflict. [ABSTRACT FROM AUTHOR]